/* save to nifti
 *
 * 5/7/18
 * 	- from fitssave.c
 * 9/9/19
 * 	- use double for all floating point scalar metadata, like other loaders
 */

/*

	This file is part of VIPS.

	VIPS is free software; you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	02110-1301  USA

 */

/*

	These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk

 */

/*
#define DEBUG_VERBOSE
#define DEBUG
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <vips/vips.h>

#ifdef HAVE_NIFTI

#include <nifti1_io.h>

#include "pforeign.h"

typedef struct _VipsForeignSaveNifti {
	VipsForeignSave parent_object;

	/* Filename for save.
	 */
	char *filename;

	nifti_image *nim;

} VipsForeignSaveNifti;

typedef VipsForeignSaveClass VipsForeignSaveNiftiClass;

G_DEFINE_TYPE(VipsForeignSaveNifti, vips_foreign_save_nifti,
	VIPS_TYPE_FOREIGN_SAVE);

static void
vips_foreign_save_nifti_dispose(GObject *gobject)
{
	VipsForeignSaveNifti *nifti = (VipsForeignSaveNifti *) gobject;

	VIPS_FREEF(nifti_image_free, nifti->nim);

	G_OBJECT_CLASS(vips_foreign_save_nifti_parent_class)->dispose(gobject);
}

/* Make ->nim from the vips header fields.
 */
static int
vips_foreign_save_nifti_header_vips(VipsForeignSaveNifti *nifti,
	VipsImage *image)
{
	VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(nifti);

	int dims[8];
	int datatype;
	int i;

	/* Most nifti images have this defaulted as 1.
	 */
	for (i = 0; i < VIPS_NUMBER(dims); i++)
		dims[i] = 1;

	dims[0] = 2;
	dims[1] = image->Xsize;
	dims[2] = vips_image_get_page_height(image);

	/* Multipage image?
	 */
	if (dims[2] < image->Ysize) {
		dims[0] = 3;
		dims[3] = image->Ysize / dims[2];
	}

	datatype = vips__foreign_nifti_BandFmt2datatype(image->BandFmt);
	if (datatype == -1) {
		vips_error(class->nickname,
			"%s", _("unsupported libvips image type"));
		return -1;
	}

	if (image->Bands > 1) {
		if (image->BandFmt != VIPS_FORMAT_UCHAR) {
			vips_error(class->nickname,
				"%s", _("8-bit colour images only"));
			return -1;
		}

		if (image->Bands == 3)
			datatype = DT_RGB;
		else if (image->Bands == 4)
			datatype = DT_RGBA32;
		else {
			vips_error(class->nickname,
				"%s", _("3 or 4 band colour images only"));
			return -1;
		}
	}

	if (!(nifti->nim = nifti_make_new_nim(dims, datatype, FALSE)))
		return -1;

	nifti->nim->dx = 1.0 / image->Xres;
	nifti->nim->dy = 1.0 / image->Yres;
	nifti->nim->dz = 1.0 / image->Yres;
	nifti->nim->xyz_units = NIFTI_UNITS_MM;

	g_snprintf(nifti->nim->descrip, sizeof(nifti->nim->descrip),
		"libvips-%s", VIPS_VERSION);

	/* All other fields can stay at their default value.
	 */

	return 0;
}

typedef struct _VipsNdimInfo {
	VipsImage *image;
	nifti_image *nim;
	int *dims;
	int n;
} VipsNdimInfo;

static void *
vips_foreign_save_nifti_set_dims(const char *name,
	GValue *value, glong offset, void *a, void *b)
{
	VipsNdimInfo *info = (VipsNdimInfo *) a;

	/* The first 8 members are the dims fields.
	 */
	if (info->n < 8) {
		char vips_name[256];
		int i;

		g_snprintf(vips_name, 256, "nifti-%s", name);
		if (vips_image_get_int(info->image, vips_name, &i) ||
			i <= 0 ||
			i >= VIPS_MAX_COORD)
			return info;
		info->dims[info->n] = i;
	}

	info->n += 1;

	return NULL;
}

/* How I wish glib had something like this :( Just implement the ones we need
 * for vips_foreign_nifti_fields above.
 */
static void
vips_gvalue_write(GValue *value, void *p)
{
	switch (G_VALUE_TYPE(value)) {
	case G_TYPE_INT:
		*((int *) p) = g_value_get_int(value);
		break;

	case G_TYPE_DOUBLE:
		*((float *) p) = g_value_get_double(value);
		break;

	default:
		g_warning("vips_gvalue_write: unsupported GType %s",
			g_type_name(G_VALUE_TYPE(value)));
	}
}

static void *
vips_foreign_save_nifti_set_fields(const char *name,
	GValue *value, glong offset, void *a, void *b)
{
	VipsNdimInfo *info = (VipsNdimInfo *) a;

	/* The first 8 members are the dims fields. We set them above ^^^ --
	 * do the others in this pass.
	 */
	if (info->n >= 8) {
		char vips_name[256];
		GValue value_copy = G_VALUE_INIT;

		g_snprintf(vips_name, 256, "nifti-%s", name);
		if (vips_image_get(info->image, vips_name, &value_copy))
			return info;
		vips_gvalue_write(&value_copy, (char *) info->nim + offset);
		g_value_unset(&value_copy);
	}

	info->n += 1;

	return NULL;
}

static void *
vips_foreign_save_nifti_ext(VipsImage *image,
	const char *field, GValue *value, void *a)
{
	nifti_image *nim = (nifti_image *) a;

	int i;
	int ecode;
	char *data;
	size_t length;

	if (!vips_isprefix("nifti-ext-", field))
		return NULL;

	/* The name is "nifti-ext-N-XX" where N is the index (discard this)
	 * and XX is the nifti ext ecode.
	 */
	if (sscanf(field, "nifti-ext-%d-%d", &i, &ecode) != 2) {
		vips_error("niftisave",
			"%s", _("bad nifti-ext- field name"));
		return image;
	}

	if (vips_image_get_blob(image, field, (void *) &data, &length))
		return image;

	if (nifti_add_extension(nim, data, length, ecode)) {
		vips_error("niftisave",
			"%s", _("unable to attach nifti ext"));
		return image;
	}

	return NULL;
}

/* Make ->nim from the nifti- fields.
 */
static int
vips_foreign_save_nifti_header_nifti(VipsForeignSaveNifti *nifti,
	VipsImage *image)
{
	VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(nifti);

	VipsNdimInfo info;
	int dims[8];
	int datatype;
	guint height;
	int i;

	/* Most nifti images have this defaulted as 1.
	 */
	for (i = 0; i < VIPS_NUMBER(dims); i++)
		dims[i] = 1;

	info.image = image;
	info.dims = dims;
	info.n = 0;
	if (vips__foreign_nifti_map(
			vips_foreign_save_nifti_set_dims, &info, NULL))
		return -1;

	/* page-height overrides ny if it makes sense. This might not be
	 * correct :(
	 */
	dims[2] = vips_image_get_page_height(image);

	/* Multipage image?
	 */
	if (dims[2] < image->Ysize) {
		dims[0] = 3;
		dims[3] = image->Ysize / dims[2];
	}

	height = 1;
	for (i = 2; i < VIPS_NUMBER(dims) && i < dims[0] + 1; i++)
		if (!g_uint_checked_mul(&height, height, dims[i])) {
			vips_error(class->nickname,
				"%s", _("dimension overflow"));
			return 0;
		}
	if (image->Xsize != dims[1] ||
		image->Ysize != height) {
		vips_error(class->nickname,
			"%s", _("bad image dimensions"));
		return -1;
	}

	datatype = vips__foreign_nifti_BandFmt2datatype(image->BandFmt);
	if (datatype == -1) {
		vips_error(class->nickname,
			"%s", _("unsupported libvips image type"));
		return -1;
	}

	if (!(nifti->nim = nifti_make_new_nim(dims, datatype, FALSE)))
		return -1;

	info.image = image;
	info.nim = nifti->nim;
	info.n = 0;
	if (vips__foreign_nifti_map(
			vips_foreign_save_nifti_set_fields, &info, NULL))
		return -1;

	/* Attach any ext blocks.
	 */
	if (vips_image_map(image,
			(VipsImageMapFn) vips_foreign_save_nifti_ext, nifti->nim))
		return -1;

	return 0;
}

static int
vips_foreign_save_nifti_build(VipsObject *object)
{
	VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(object);
	VipsForeignSave *save = (VipsForeignSave *) object;
	VipsForeignSaveNifti *nifti = (VipsForeignSaveNifti *) object;

	if (VIPS_OBJECT_CLASS(vips_foreign_save_nifti_parent_class)->build(object))
		return -1;

	/* This could be an image (indirectly) from niftiload, or something
	 * like OME_TIFF, which does not have all the "nifti-ndim" fields.
	 *
	 * If it doesn't look like a nifti, try to make a nifti header from
	 * what we have.
	 */
	if (vips_image_get_typeof(save->ready, "nifti-ndim")) {
		if (vips_foreign_save_nifti_header_nifti(nifti, save->ready))
			return -1;
	}
	else {
		if (vips_foreign_save_nifti_header_vips(nifti, save->ready))
			return -1;
	}

	/* set ext, plus other stuff
	 */

	if (nifti_set_filenames(nifti->nim, nifti->filename, FALSE, TRUE)) {
		vips_error(class->nickname,
			"%s", _("unable to set nifti filename"));
		return -1;
	}

	if (!(nifti->nim->data =
				vips_image_write_to_memory(save->ready, NULL)))
		return -1;

	/* No return code!??!?!!
	 */
	nifti_image_write(nifti->nim);

	/* We must free and NULL the pointer or nifti will try to free it for
	 * us.
	 */
	VIPS_FREE(nifti->nim->data);

	return 0;
}

/* Save a bit of typing.
 */
#define UC VIPS_FORMAT_UCHAR
#define C VIPS_FORMAT_CHAR
#define US VIPS_FORMAT_USHORT
#define S VIPS_FORMAT_SHORT
#define UI VIPS_FORMAT_UINT
#define I VIPS_FORMAT_INT
#define F VIPS_FORMAT_FLOAT
#define X VIPS_FORMAT_COMPLEX
#define D VIPS_FORMAT_DOUBLE
#define DX VIPS_FORMAT_DPCOMPLEX

static VipsBandFormat vips_nifti_bandfmt[10] = {
	/* Band format:  UC  C  US  S  UI  I  F  X  D  DX */
	/* Promotion: */ UC, C, US, S, UI, I, F, X, D, DX
};

static void
vips_foreign_save_nifti_class_init(VipsForeignSaveNiftiClass *class)
{
	GObjectClass *gobject_class = G_OBJECT_CLASS(class);
	VipsObjectClass *object_class = (VipsObjectClass *) class;
	VipsOperationClass *operation_class = VIPS_OPERATION_CLASS(class);
	VipsForeignClass *foreign_class = (VipsForeignClass *) class;
	VipsForeignSaveClass *save_class = (VipsForeignSaveClass *) class;

	gobject_class->dispose = vips_foreign_save_nifti_dispose;
	gobject_class->set_property = vips_object_set_property;
	gobject_class->get_property = vips_object_get_property;

	object_class->nickname = "niftisave";
	object_class->description = _("save image to nifti file");
	object_class->build = vips_foreign_save_nifti_build;

	/* nificlib has not been fuzzed, so should not be used with
	 * untrusted input unless you are very careful.
	 */
	operation_class->flags |= VIPS_OPERATION_UNTRUSTED;

	foreign_class->suffs = vips_foreign_nifti_suffs;

	save_class->saveable = VIPS_SAVEABLE_ANY;
	save_class->format_table = vips_nifti_bandfmt;

	VIPS_ARG_STRING(class, "filename", 1,
		_("Filename"),
		_("Filename to save to"),
		VIPS_ARGUMENT_REQUIRED_INPUT,
		G_STRUCT_OFFSET(VipsForeignSaveNifti, filename),
		NULL);
}

static void
vips_foreign_save_nifti_init(VipsForeignSaveNifti *nifti)
{
}

#endif /*HAVE_NIFTI*/

/**
 * vips_niftisave: (method)
 * @in: image to save
 * @filename: file to write to
 * @...: %NULL-terminated list of optional named arguments
 *
 * Write a VIPS image to a file in NIFTI format.
 *
 * Use the various NIFTI suffixes to pick the nifti save format.
 *
 * See also: vips_image_write_to_file(), vips_niftiload().
 *
 * Returns: 0 on success, -1 on error.
 */
int
vips_niftisave(VipsImage *in, const char *filename, ...)
{
	va_list ap;
	int result;

	va_start(ap, filename);
	result = vips_call_split("niftisave", ap, in, filename);
	va_end(ap);

	return result;
}
